Reviewer #1 (Remarks to the Author):
This paper describes the scanning tunnelling microscopy imaging (STM) of a silver cluster (Ag374). To the best of my knowledge there is no report of such things to date. As such I think this paper should be published but in a specialised journal or a broad journal with reporting functions as Scientific Reports.

The significance of this paper as such is minimal. The STM does not add anything to what X-ray crystallography has shown so far also on the same cluster. In fact it requires strong support from calculation.

The STM itself has been widely published on nanoparticles by the group of Stellacci. The authors do reference a controversy there but do not comment on it an neither add to it.

The approach used is almost identical to the one described by such group in Ong et alACS Nano (non cited), and the results achieved are similar to the ones described in the same paper and in Moglianetti et al. (not cited). Their minimal difference is that they achieved these results in liquid nitrogen and helium temperature, but low temperature results were described in Biscarini et al. (not cited).

Given the scant discussion in the paper (lacks any point) and the two major objections report, I suggest rejection.

The other, more supportive reports, and the response from the authors, can be downloaded from Nature Communications.

At the 2018 American Chemical Society National Meeting in Boston, I asked a question to Chad Mirkin after his talk on Spherical Nucleic Acids. This is what I said:

In science, we need to share the bad news as well as the good news. In your introduction you mentioned four clinical trials. One of them has reported. It showed no efficacy and Purdue Pharma which was supposed to develop the drug decided not to pursue further. You also said that 1600 forms of NanoFlares were commercially available. This is not true anymore as the distributor has pulled the product because it does not work. Finally, I have a question: what is the percentage of nanoparticles that escape the endosome.

I had written my question and I asked exactly this although not in one block as he started answering before I had made all my points. He became very angry. The exchange lasted maybe 5 minutes. Towards the end he said that no one is reading my blog (who cares), that no one agrees with me, he called me a “scientific zealot” and a “scientific terrorist”. The packed room was shell shocked. We then moved swiftly to the next talk.

Two group leaders, one from North America and the other one from Europe, came to me afterwards.

Group leader 1:

Science is ever evolving and evidenced based. The evidence is gathered by first starting to ask questions. I witnessed an interaction between two scientists. One asks his questions gracefully and one responding in a manner unbecoming of a Linus Pauling Medalist. It took courage to stand in front of a packed room of scientists and peers to ask those questions that deserved an answer in a non-aggressive manner. It took even more courage to not become reactive when the respondent is aggressive and belittling. I certainly commended Raphael Levy for how he handled the aggressive response from Chad Mirkin. Even in disagreements, you can respond in a more professional manner. Not only is name calling not appropriate, revealing the outcomes of reviewers opinions from a confidential peer-review process is unprofessional and unethical.*

Lesson learned: Hold your self to a high standard and integrity.

Group leader 2:

Many conferences suffer from interesting discussions after a talk in such way that there are questions and there are answers. So far so good. Only in rare cases, a critical mind starts a discussion, or ask questions which imply some disagreement with the presented facts. Here I was surprised how a renowned expert like Chad Mirkin got in rage by such questions of Raphael Levy and how unprofessional his reaction was. It was not science any longer, it was a personal aggression, and this raises the question why Chad Mirkin acted like this? I do not think that this strategy helps to get more acceptance by the audience. I tribute to Raphael Levy afterwards, because I think science needs critical minds, and one should not be calm because of the fear to get attacked by a speaker. Science is full of statements how well everything works, and optimism is the fuel to keep research running. There is nothing wrong with this, but definitely one also need critical questions to make progress, and what we don’t need is unprofessional behavior and discreditation.

* Group leader 1 refers here to the outcome of the reviews of this article which you can read on ChemrXiv and which was (predictably) rejected by Nature Biomedical Engineering. During the incident Chad Mirkin used these reviews to attack me.

“Calling a fellow researcher a “scientific terrorist” for raising concerns and asking a question (even if you disagree with them) is shocking. Sorry to hear that there wasn’t any real discussion instead, would’ve been interesting.” @bearore

“Surprised this isn’t getting more pub. One must wonder at what point does one’s ego/reputation become more important than the science, which ABSOLUTELY must include the bad with the good.” @Ben_Jimi440

“Keep fighting the good fight tenaciously, Raphael. Like the detectives in those old film noir shows… ” @drheaddamage

The great answer is… review them! I issued a call to review our preprint before it comes out and I have now sent the article to a number of colleagues across the world. I am very much looking forward to their comments good or bad. The comments will be posted on PubPeer. If you have some time on your hands this Friday or over the weekend to look at the paper, drop me an email and I will also send you a preview copy.

Yeo et al corresponding authors were provided with a copy of our preprint two weeks ago but unfortunately they have not responded. I hope they will post comments on PubPeer. We are planning to subsequently submit a version (hopefully improved thanks to the comments) to Nature Biomedical Engineering. It is however sometime rather difficult to debate the scientific literature through the official channels of traditional journals so this route via preprint will accelerate this important discussion.

That’s the great answer to people saying that #preprints are not peer-reviewed! Review them – and they won’t be different from any other publications. 😀https://t.co/2FTEoVfwVc

« Selon que vous serez puissant ou misérable, les jugements de cour vous rendront blanc ou noir » [1] [Depending on your social height, The law will see your crime as black—or else as white.] Thus concludes the Fable, by Jean de La Fontaine, The Animals sick of the plague : the donkey, guilty of the theft of a few blades of grass, is condemned to death, whilst the Lion and other powerful animals guilty of much more serious crimes are treated to praise and flattery. It is tempting and comforting to think that scientific judgments are of an altogether different nature. Seen in this light, science would reside outside of power struggles and the few mishaps (mistakes, frauds, conflicts of interest) would be rapidly corrected since the reality of the material world would quickly come back to us through experimental results if we were to try to ignore it for too long. The truth is however very different. A large fraction of published scientific results cannot be reproduced. It is not a few mishaps but structural problems which affect the foundations of the scientific enterprise [2, 3]. Peer evaluations seems to encourage the publication of extraordinary stories in high impact factor journals rather than careful and rigorous experimental studies. Contradictory or “negative” data are rarely published: scientific journals are not really interested, and us, scientists, are not particularly motivated by publicly stating our doubts on the work of colleagues who could be in charge of evaluating our next article or grant application. It is particularly urgent to repair our knowledge production system because science is at the center of numerous challenges critical for the future of human beings and the planet. The (real) problems of reproducibility have already been harnessed by lobbies to attack the credibility of scientists [4]. After the election for president of the largest scientific and military power of the world of a man who denies climate change, is very positive about the use of the atomic bomb, and, more broadly wages an open war against science and truth [5], we have a paramount need for science to be open, robust, capable of defending its independence, integrity and universal values. This seems a distant prospect.

The near absence of critical discussion in the scientific literature in many areas of science could make us forget that controversies are an essential aspect of the quest for knowledge, allowing to identify weak points of experiments and theories, thus enabling to consolidate or invalidate them [6]. They are consubstantial to the scientific practice [7]. The analysis of controversies is also a tool to “symmetrically map” the actors to better understand the roles of individuals and social processes [8]. In this piece, I describe three recent controversies in my area of research: gold nanoparticles applied to biology and medicine. This is no “symmetric map”: I am not a neutral observer but a scientist active, to various degrees, in each of those. I am trying nevertheless to draw some lessons and suggestions to improve the ways we work as scientists.

Stripy Nanoparticles

In 2004, Francesco Stellacci’s group at the Massachusetts Institute of Technology (MIT) published in the prestigious journal Nature Materials an article describing gold nanoparticles covered by a mixture of two molecules that self-assemble to form stripes that are observed by scanning probe microscopy [9]. This article and the numerous other ones that will follow in the same journal and in others just as prestigious such as the Journal of the American Chemical Society [10], Science [11] and Proceedings of the National Academy of Sciences (PNAS) [12], suggest that, thanks to their stripes, these nanoparticles have unique properties in terms of wetting, self-organization, interaction with proteins, penetration in cells, with lots of potential applications for biomolecular sensing, or even drug delivery. These articles certainly contributes to the progress of their authors’ careers, but the stripes are an experimental artefact well known by users of scanning probe microscopy. How to explain then that more than 20 “stripy” articles were published between 2004 and 2012? It is obvious that specialists (and even enlightened amateurs) had identified the problem as early as 2004. Yet, the articles and reviews of that period show no sign of it. One now knows that Predrag Djuranovic has been the first to engage into a scientific investigation aiming at testing, and eventually, contesting, the evidence for the the existence of the stripes. In 2005, this rigorous and brave scientist was a student in Francesco Stellacci’s lab. His experimental results and numerical simulation showing how the stripes originate from a poorly adjusted feedback control system were unambiguous but MIT ensured that these results would remain secret [13]. In 2007, I submitted a technical comment responding to the Science article. This first attempt, limited in its scope to the Science article itself, was unsuccessful: Science did ask Francesco Stellacci to respond but then decided not to publish the exchange of views [14]. In 2008, a new article from the MIT group, again in Nature Materials, report that, thanks to their stripes, these nanoparticles can cross the cell membrane and directly access the cytosol [15]. This is accompanied by a commentary entitled “Particles slip cell security” [16]. After discussions with several of my students, we decide to propose a more exhaustive answer. A few months later, the article “Stripy Nanoparticles Revisited” is ready. It includes a new analysis of the stripy images concluding that the stripes are a scanning artefact as well as a critical discussion of the physicochemical and biological properties which, together with experimental results, contradict the claim of direct access to the interior of cells. The article is first submitted to Nature Materials (rejected), then NanoLetters (rejected), and, finally, Small… where it is published after an editorial process that lasted three years [17-19]. The publication of our article, in November 2012, does not end the controversy. Instead, it expands in the scientific literature (a little) and it also takes new forms (in particular on my blog and others [20-23]). Problems with the reuse of images in different publications emerge and eventually lead to two corrections ([12] and [15]). After a number of requests, Philip Moriarty and Julian Stirling (School of Physics and Astronomy, university of Nottingham, UK) are given access to the original data of the 2004 article. They demonstrate, among other things, that the stripes are present in the entire image, i.e. even between the gold nanoparticles [24], a conclusion still rejected by Francesco Stellacci [25].

Homeopathic nanoparticles

The laboratory of Molly Stevens at Imperial College is one of the most prestigious in the field of biomaterials. In 2012, two articles from the group relate the particularly interesting properties of nanoparticles for diagnostic applications. The first one, published in Nature Materials, reports a phenomenon which is entirely extraordinary in which the signal detected increases when the concentration of molecules to detect decreases (“inverse sensitivity”) [26]. Even more incredible, this phenomenon extends to the point where there is less than a molecule of enzyme, on average, in the volume under study. The second article published in Nature Nanotechnology goes further : no need for instruments, the detection of concentration of analytes in the same range is achieved thanks to a colour change visible with the naked eye [27]. Detailed critiques of these articles are available on the website PubPeer [28, 29] as well as in a preprint authored by Boris Barbour; the objections are both simple and profound but the authors have chosen not to respond. One can note that the Avogadro number includes lots of zeros (630 000 000 000 000 000 000 000) and that the detection of a macroscopic change of property due to the presence of a single molecule is therefore an achievement that requires extremely solid proofs. One of the posts on PubPeer indicates that someone contacted the Editor of Nature Nanotechnology in January 2013, but, four years later, no doubts are expressed on the journal website, in the traditional scientific literature nor in the newspapers that had covered this story (e.g. Le Monde and the Daily Mail) when it was initially published [30, 31].

Spherical Nucleic Acids

The laboratory of Chad Mirkin at Northwestern University (USA) is one of the most prestigious in the field of nanosciences applied to biology and medicine. One major theme of their research are the Spherical Nucleic Acids (SNAs), a term introduced by Mirkin to describe gold nanoparticles functionalised with DNA (or RNA) strands. These SNAs are supposed to have properties very different from linear DNA [32]. In particular, they can access the cytosol of live cells, where they could detect and regulate, the presence and quantity of mRNAs. One could ask why this solution did not appear during evolution : to access the cell machinery, viruses and bacteria would have only needed to package themselves within their genetic materials. The first articles (in Science [33], the Journal of the Americal Chemical Society [34], NanoLetters [35], ACS Nano [36]) proposing this surprising theory do no mention the mechanism of the SNAs into cells whatsover. The following one, e.g. [37], propose that the particles enter by endocytosis, but do not explain the mechanism by which the SNAs would escape endosomes. After several dozens of articles on this topic, the proportion of particles reaching the cytosol is still to be measured and reported (in spite of the fact that gold nanoparticles have been used since the 1950s to study intracellular trafficking; such a study would not be difficult). One article from the Mirkin group suggests that SNAs are degraded in the endosomes and that a “small unquantifiable portion escapes […]” [38]. Nevertheless, the particles are now commercially available under the name SmartFlares (Merck Millipore) to detect RNA inside cells. We have studied the entry of nanoparticles in cells and their ability to detect RNA. Given our difficult experience with the publication of Stripy Nanoparticle Revisited, we decided to adopt a different strategy. The project has been open and we have shared our results in quasi real time on our blog. In contradiction with the descriptions made by Mirkin and by Merck Millipore, we have observed that the SmartFlares were degraded in endosomes and were not able to detect mRNA. Mirroring the tale of Predrag Djuranovic and the stripy nanoparticles, we were not the first to have doubts about the technology: Luke Armstrong, who had been in charge of developing the SmartFlares at Merck Millipore in California (before leaving the company) had reached the same conclusion [39]. To ensure speedy publication and transparency, we published our article on the (not so prestigious) ScienceOpen platform where peer review occurs after publication [40]. We invited comments by Mirkin to no avail. Another article by the same group in PNAS describe a new version of the SmartFlares [41]. Our analysis of the raw data (obtained after multiple insistent requests) show that the signal comes from endosomes. Our letter submitted to PNAS has been rejected by the editorial board because it “[did] not contribute significantly to the discussion of this paper” [42].

Morals

Access to raw data is essential and guaranteed by clear rules adopted by Universities, scientific journals and funding agencies. It is therefore generally possible to access data with some efforts. It is obviously preferable to publish data at the same time as the articles. This is already the norm for some categories of results and it should become generalised. Researchers should also adopt the Manifesto for reproducible research [43]. The tools are in place to improve the practice of science.

Evaluations of science and scientists must imperatively be based on a critical analysis of their work and the robustness or their results, not on the prestige of the institutions or journals. This requires a change of mind and a clear commitment from researchers who are in positions of power, i.e. everyone who features on promotion or recruitment committees. To say that an article is good because it has been published in a prestigious journal is a moral and logical error which needs to be challenged.

Institutions and scientific journals are not motivated by the quest for scientific truth. The decisisons taken by MIT (keeping Predrag Djuranovic’s findings secret), by Nature Materials (not publishing the exchange with Francesco Stellacci [14]), and by PNAS (not publishing [42]) have directly impacted progress of knowledge. These institutions have commendable principles but, in practice, they aim first at defending their reputation and finances [44]. The latter objective only partially aligns with scientific progress which requires rapid and open discussion of results and conclusions. The Worldwide Web, invented for the sharing of science, enables this discussion. Researchers therefore should embrace the following tools: 1) Pubpeer to comment on articles; 2) Preprints to publish rapidly, minimise the influence of editors, and, dissociate publication, i.e. sharing of information, from evaluation, i.e. peer review; 3) Social networks, e.g. Twitter and blogs, which constitute an ongoing scientific conference to discuss experiments, results, methods, analyses, and new publications.

Acknowledgements: I thank Marianne Noel (IFRIS) for her critical reading of this piece, and, Marianne Lévy for comments on the grammar and style [French version] very necessary after 14 years in an English-speaking country…

Conflicts of interest: The author declares that he has no conflict of interest related to this article.

This post is dedicated to Paul Picard, my grand dad, who was the oldest reader of my blog. He was 17 (and Jewish) in 1939 so he did not get the chance to go to University. He passed away on the first of October 2016. More on his life here (in French) and some of his paintings (and several that he inspired to his grandchildren and great-grandchildren). The header of my blog is from a painting he did for me.

A few recent events of vastly different importance eventually triggered this post.

A (non-scientist) friend asked my expert opinion about a campaign by a French environmental NGO seeking to raise money to challenge the use of nanoparticles such as E171 in foods. E171 receives episodic alarmist coverage, some of which were debunked by Andrew Maynard in 2014. The present campaign key dramatic science quote “avecle dioxyde de titane, on se retrouve dans la même situation qu’avec l’amiante il y a 40 ans {with titanium dioxide, we are in the same situation than we were with asbestos 40 years ago}” is from Professor Jürg Tschopp. It comes from an old media interview (2011, RTS) that followed a publication in PNAS. We cannot ask Professor Tschopp what he thinks of the use of this 5 years old quote: unfortunately he died shortly after the PNAS publication. The interpretation of this article has been questioned since: it seems likely that the observed toxicity was due to endotoxin contamination rather than the nanomaterials themselves. There is on the topic of nanoparticles a high level of misinformation and fear that finds its origins (in part) in how the scientific enterprise is run today. Incentives are to publish dramatic results in high impact factor journals which lead many scientists to vastly exaggerate both the risks and the potential of their nanomaterials of choice. The result is that we build myths instead of solid reproducible foundations, we spread disproportionate fears and hopes instead of sharing questions and knowledge. When it comes to E171 additives in foods, the consequences of basing decisions on flawed evidence are limited. After all, even if the campaign is successful, it will only result in M&M’s not being quite as shiny.

I have been worried for some time that the crisis of the scientific enterprise illustrated by this anecdote may affect the confidence of the public in science. In a way, it should; the problems are real, lead to a waste of public money, and, they slow down progress. In another way, technological (including healthcare) progress based on scientific findings has been phenomenal and there are so many critical issues where expertise and evidence are needed to face pressing humanities’ problems that such a loss of confidence would have grave detrimental effects. Last week, in the Spectator, Donna Laframboise published an article entitled “How many scientific papers just aren’t true?Enough that basing government policy on ‘peer-reviewed studies’ isn’t all it’s cracked up to be“. The article starts by a rather typical and justified critique of peer review, citing (peer-reviewed) evidence, and then, moves swiftly to climate change seeking to undermine the enormous solid body of work on man-made climate change. It just happens that Donna Laframboise is working for “a think-tank that has become the UK’s most prominent source of climate-change denial“.

Implementation of the Principle of the Universality of Science is fundamental to scientific progress. This Principle embodies freedom of movement, association, expression and communication for scientists, as well as equitable access to data, information and research materials. These freedoms are highly valued by the scientific community and generally well accepted by governments and policy makers. Hence, scientists are normally able to travel to international meetings, associate with colleagues and freely express their opinions regardless of factors such as ethnic origin, religion, citizenship, language, political stance, gender, sex or age. However, this is not always the case and so it is important to have mechanisms in place at the local, national and international levels to monitor compliance with this principle and intervene when breaches occur. The International Council for Science (ICSU) and its global network of Members provide one such mechanism to which individual scientists can turn for assistance. The Principle of the Universality of Science focuses on scientific rights and freedoms but implicit in these are a number of responsibilities. Individual scientists have a responsibility to conduct their work with honesty, integrity, openness and respect, and a collective responsibility to maximize the benefit and minimize the misuse of science for society as a whole. Balancing freedoms and responsibilities is not always a straightforward process. For example, openness and sharing of data and materials may be in conflict with a scientist’s desire to maintain a competitive edge or an employer’s requirements for protecting intellectual property. In some situations, for example during wars, or in specific areas of research, such as development of global surveillance technologies, the appropriate balance between freedoms and responsibilities can be extremely difficult to define and maintain. The benefits of science for human well-being and development are widely accepted. The increased average human lifespan in most parts of the world over the past century can be attributed, more or less directly, to scientific progress. At the same time, it has to be acknowledged that technologies arising from science can inadvertently have adverse effects on people and the environment. Moreover, the deliberate misuse of science can potentially have catastrophic effects. There is an increasing recognition by the scientific community that it needs to more fully engage societal stakeholders in explaining, developing and implementing research agendas. A central aspect of ensuring the freedoms of scientists and the longer term future of science is not only conducting science responsibly but being able to publicly demonstrate that science is being conducted responsibly. Individual scientists, their associated institutions, employers, funders and representative bodies, such as ICSU, have a shared role in both protecting the freedoms and propagating the responsibilities of scientists. This is a role that needs to be explicitly acknowledged and embraced. It is likely to be an increasingly demanding role in the future.

It is urgent that we, scientists, reclaim these values of humanity, integrity and openness and make them central (and visibly so) in our Universities. To ensure this transformation occurs, we must act individually and as groups so that scientists are evaluated on their application of these principles. The absurd publication system where we (the taxpayer) pay millions of £$€ to commercial publishers to share hide results that we (scientists) have acquired, evaluated and edited must end. There are some very encouraging and inspiring open science moves coming from the EU which aim explicitely at making “research more open, global, collaborative, creative and closer to society“. We must embrace and amplify these moves in our Universities. And, as many, e.g. @sazzels19 and @Stephen_curry have said, now more than ever, we need to do public engagement work, not with an advertising aim, but with a truly humanist agenda of encouraging curiosity, critical thinking, debates around technological progress and the wonders of the world.

Nature Publishing Group encouragement of replications and discussions of their own published studies is a very welcome move. Seven years ago, I wrote a letter (accompanying a submission) to the Editor of Nature Materials. The last paragraph of that letter read: “The possibility of refuting existing data and theories is an important condition of progress of scientific knowledge. The high-impact publication of wrong results can have a real impact on research activities and funding priorities. There is no doubt that the series of papers revisited in this Report contribute to shape the current scientific landscape in this area of science and that their refutation will have a large impact.” [1]

The submission was “Stripy Nanoparticles Revisited” and it took three more years to publish it… in another journal; meanwhile Nature Materials continued to publish findings based on the original flawed paper [2]. The ensuing, finally public (after three years in the secret of peer review), discussions on blogs, news commentary and follow up articles were certainly very informative on the absolute necessity of changing the ways we do science to ensure a more rapid discussion of research results [3].

One of the lessons I draw from this adventure is that the traditional publishing system is, at best ill suited (e.g. Small: three years delay), or at worst (e.g. Nature Materials) completely reluctant at considering replications or challenges to their published findings. Therefore, I am now using PrePrints (e.g. to publish a letter PNAS won’t share with their readers [4]), PubPeer and journals such as ScienceOpen where publication happens immediately and peer review follows [5].

So whilst I warmly welcome this editorial, it will need a little more to convince me that it is not a complete waste of time to use the traditional channels to open discussions of published results.

Proceedings of the National Academy of Sciences (PNAS) has two paths for submission of research articles, one standard and one less so, the famous contributed track where the submitting author has to be a member of the National Academy of Sciences of the United States of America. Peter Aldhous reviewed in 2014 this inside track and those who use it more often. He describes the contributed track as follows: “This unusual process allows authors to choose who will review their paper and how to respond to those reviewers’ comments“.

There are two elements of transparency and accountability to counterbalance this conflict of interest of having an author acting as the editor of their own article: it is recorded on the paper that it is a contributed paper, and, the names of the referees (chosen by the author) are also published. It is interesting (maybe) to note that this ancient house of PNAS has a system there which is pretty similar to what has been recently proposed as a disruptive innovation in scientific publishing by Jan Velterop and implemented by ScienceOpen, i.e. peer review by endorsement (PRO). There are a couple of differences. The first one is that PRO at ScienceOpen is open to everyone, not just National Academy members. The second one is that not just the names of the reviewers, but also the content of the reviews that is shared in PRO.

As readers of this blog will know, David Mason and I have recently challenged a particular contributed PNAS paper by the Mirkin group on StickyFlares. The discussion can be found at PubPeer (the authors did not engage). We requested some data which (after some efforts) we eventually obtained. We wrote a letter to the Editor. Which was eventually rejected by Inder Verma editor of PNAS. The letter is available at BiorXiv.

Given that neither PubPeer nor the PNAS letter to editor enabled to get any answers from the authors to our substantial criticism, we were curious to know if any of the referees had maybe raised similar issues and, if yes, how the authors had replied. Dave therefore wrote to the referees to ask whether they would share their reports. The response was negative; they could not share their reports because “referee comments from peer review have to be kept confidential as it is an essential part of maintaining the integrity of the peer review process“. I was rather surprised by this response and was moved to write the following:

01/10/2015

Dear Shana, Chris

I am Raphael; Dave is a member of my group. Apologies for pitching in and for a rather long response!

Thank you both for your replies. [paragraph edited out about the issue of whether the PNAS guidelines on choice of reviewers were followed; see the PubPeer discussion for more]

I fully share your commitment to defend the integrity of the review process, but I would urge to you to reconsider your decision to keep your comments confidential, precisely because it does not serve that very commendable aim.

It is worth considering for a moment what is the role of confidentiality and anonymity in the peer review process, and also who is in charge of guaranteeing that confidentiality and anonymity. In a traditional peer review process, the reports are confidential and anonymous: the justification is the protection of the reviewers from potential reprisals if they were to write a very critical review. The editors are in charge of protecting the confidentiality and anonymity: this is part of the contract between the editor and the reviewers. If the editor was to publish the reviews or/and, worse, reveal their identity, he/she would breach that contract and this would significantly affect the trust between future reviewers and the journal. I have myself pondered on publishing on my blog the reviews of a (rejected) submission of one of my papers, and was eventually convinced (though I am still entirely sure this was the right decision) not to do so by the detailed comments of an editor who did point out that the reviewers expected their reviews to remain confidential and that I would therefore breach their trust by doing so [1]. It is however a completely different matter for reviewers who can decide to forego their right to anonymity both immediately at the stage of the review process (“signing reviews”, usually, precisely with the motivation of increasing transparency and integrity of the review process), or later, for various reasons (nearly 200 000 examples at Publons, a site that enables and encourages reviewers to share their reports [2-3]). A recent prominent example of a reviewer sharing her reviews (on PubPeer) is Vicki Vance, who had reviewed several of the papers of Olivier Voinnet and noted serious problems (they were nevertheless published) [4]. I have never heard anyone suggesting that a reviewer who would decide to share their reviews of a paper after publication, i.e. their own scholarly evaluation of published work, would be damaging the integrity of the peer review process. I also really fail to see by what mechanism it could do so.

Obviously, the PNAS “contributed submission” path is another can of worms. Many would argue that it is in itself damaging to the integrity of the peer review process with this very unusual situation where an author chose its reviewers. In this specific case, it is hard to see any justification at all for the confidentiality of the reviews: it does not serve to protect the reviewers from potential reprisals from the author since the author has chosen its referees in the first place. The only thing it does is prevent the public (and in particular other scientists) to benefit from the insights that would be provided by sharing the reviews. I would argue that here even more than in any other case, sharing the reviews would be the best way to protect the integrity of the peer review process and therefore I hope you will reconsider,